In the following, $time is the date in seconds since the UNIX epoch. I'm converting it back to a string (in the print statement) for testing purposes.

use Time::Local;

%MONTHS_LOOKUP = (
   Jan => 0,
   Feb => 1,
   Mar => 2,
   Apr => 3,
  #...
);

my $date = 'Apr 29 13:54:10';

$date =~ /^(.{3}) (.{2}) (.{2}):(.{2}):(.{2})$/
or die("Bad date\n");

my $time = timelocal($5, $4, $3, $2, $MONTHS_LOOKUP{$1}, 2005);

print(scalar(localtime($time)), "\n");
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The following variation might be faster, because it doesn't check the validity of the inputs:

use Time::Local qw( timelocal_nocheck );

%MONTHS_LOOKUP = (
   Jan => 0,
   Feb => 1,
   Mar => 2,
   Apr => 3,
  #...
);

my $date = 'Apr 29 13:54:10';

$date =~ /^(.{3}) (.{2}) (.{2}):(.{2}):(.{2})$/
or die("Bad date\n");

my $time =
   timelocal_nocheck($5, $4, $3, $2, $MONTHS_LOOKUP{$1}, 2005);

print(scalar(localtime($time)), "\n");
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